Thiouracil-carboxylic acids for treatment of viruses

ABSTRACT

Pharmaceutical compositions comprising 2-thiouracil-4-carboxylic acid and uracil-4-carboxylic acid and their nontoxic salts or lower alkyl esters. These compositions are effective in providing a nonspecific activity against virus warts, Molluscum contagiosum, Condylomata acuminata, Herpes simplex, and Herpes zoster.

United States Patent 5 Claims, No Drawings Inventor Hermann Moor Binningen, Switzerland Appl. No. 722,183 Filed Apr. 18, 1968 Patented Sept. 21, 1971 Assignee Chemoforma A. G.

Basel-Landschalt, Switzerland Priority Apr. 19, 1967 Great Britain 18,102/67 THIOURAClL-CARBOXYLIC ACIDS FOR TREATMENT OF VIRUSES Carrara et al. Chem. Abst. Vol. 53-1959 page 7432d Primary ExaminerSam Rosen Atl0meyBacon & Thomas ABSTRACT: Pharmaceutical compositions comprising 2- thioui'acil-4-carboxylic acid and uracil-4-carboxylic acid and their nontoxic salts or lower alkyl esters. These compositions are effective in providing a nonspecific activity against virus warts, Molluscum contagiosum, Condylomata acuminata, Herpes simplex, and Herpes zoster.

THIOURACIL-CARBOXYLIC ACIDS FOR TREATMENT OF VIRUSES SUMMARY OF THE INVENTION The present invention is based upon the discovery that a useful chemotherapeutic effect in human beings can be obtained by the administration of a thiouracil-carboxylic acid, preferably 2-thiouracil-4-carboxylic acid which is the compound of formula According to one feature of the present invention, there are provided pharmaceutical or nutritional compositions for human use comprising as active ingredient a thiouracil-carboxylic acid, or a nontoxic salt or alkyl ester of a thiouracilcarboxylic acid, together with one or more carriers or excipients as herein defined.

The thiocuracil-carboxylic acid used in the compositions according to the invention is preferably a 2'thiouracil-carboxylic acid. 2-Thiouracil-4-carboxylic acid and salts and alkyl esters thereof are particularly preferred active ingredients.

By the term non-toxic as used herein in relation to the salts of thiouracil-carboxylic acids we mean such salts the cationic portions of which are physiologically compatible in the dosages used. Preferred salts include alkali metal salts such as the sodium and potassium salts, and ammonium and quaternary ammonium salts such as for example the choline salt. Preferred alkyl esters are esters in which the alkyl group is a lower alkyl group containing from one to five carbon atoms, especially a methyl or ethyl group.

The expression carriers or excipients" as used herein means any solid or liquid carrier or excipient suitable for the formulation of pharmaceutical and nutritional compositions, but does not include water or solvents alone which together with the other component or components of the composition in the concentrations in which they are present give rise to mere known solutions.

The pharmaceutical compositions according to the invention may be presented in a form suitable for oral, rectal or parenteral administration. Thus, for example, compositions for oral administration may be solid or liquid and may take the form of capsules, tablets, coated tablets, cachets, granules, powders, syrups, suspensions, etc., such compositions including carriers or excipients conveniently used in the pharmaceutical art. Suitable tabletting excipients include lactose, potato and maize starches, talc, gelatine, and stearic and silicic acids, magnesium stearate and polyvinylpyrrolidone.

For parenteral administration, the carrier or excipient may be a sterile, parenterally acceptable liquid, e.g. pyrogen-free water or an aqueous solution of polyvinylpyrrolidone, or a parenterally acceptable oil, e.g. arachis oil, contained in ampuls.

In compositions for rectal administration, the carrier may comprise a suppository base, e.g., cocoa butter or other glyceride.

ln nutritional compositions according to the invention, the carrier may be provided by a foodstuff such as for example milk powder.

Advantageously, the compositions may be formulated as dosage units, each unit being adapted to supply a fixed dose of active ingredient. Tablets, coated tablets, capsules, pills, cachets, ampuls and suppositories are examples of preferred dosage unit forms according to the invention, which con.- veniently contain from 0.1 to 100 mg., preferably 0.5 to mg., of active ingredient.

The administration of pharmaceutical and nutritional compositions according to the invention as hereinbefore defined in general assists in providing a nonspecific activity against virus warts and diseases such as for example Molluscum contagiosum, condylomata acuminata, Herpes simplex and Herpes zoster. it has been found that an improved eflect is generally obtained if the thiouracilcarboxylic acid component is administered together with a uracil-carboxylic acid or a nontoxic salt or alkyl ester thereof. The uracil-carboxylic acid is preferably uracil-4-caryoxylic acid but may also for example be provided by uracil-S-carboxylic acid, uracil-4,5- dicarboxylic acid and nontoxic salts and alkyl esters of such acids. Thus preferred compositions according to the invention contain a uracil-carboxylic acid, the particularly preferred ratio by weight of the thiouracilcarboxylic acid (or nontoxic salt or alkyl ester thereof) to uracil-carboxylic acid (or nontoxic salt or alkyl ester thereof) being from 1:1 to l:50, by weight.

It has further been found that an improved effect is generally obtained if the thiouracil-carboxylic acid component is administered together with methionine or a biological equivalent thereof such as for example hydroxymethionine or methoxy-methionine. It is thus advantageous to include in the compositions according to the invention, a proportion of methionine or other biological methylating agent, that is an agent capable of effecting the introduction of methyl groups under biological conditions. The biological methylating agents may for example be physiological methyl donors and methionine, hydroxy-methionine and methoxymethionine are of course well-known methyl donors. Other such donors include choline and S-methyl-tetrahydrofolic acid. In general, methyl donors possess a comparatively labile methyl group. Such a methyl group will generally be attached to a sulfur atom (as in methionine) or a nitrogen atom (as in choline).

Preferred compositions according to the invention contain methionine or other biological methylating agent, the ratio by weight of the thiouracil carboxylic acid (or nontoxic salt or alkyl ester thereof) to biological methylating agent being from 1:10 to l: 200, advantageously about 1: 100, by weight.

According to a further feature of the present invention, there is thus provided a pharmaceutical or nutritional composition which comprises a thiouracilcarboxylic acid or a nontoxic salt or alkyl ester of a thiouracil-carboxylic acid, together with methionine (or other biologicalmethylating agent and/or a uracil-carboylic acid (or a nontoxic salt or alkyl ester thereof).

As stated above, the administration of compositions according to the invention in general assists in providing a nonspecific activity against virus warts and diseases such as for example Molluscum contagiosum, Condylomata acuminata, Herpes simplex and Herpes zoster. Compositions containing for example 2-thiouracil-4- carboxylic acid, uracil-4-carboxylic acid and methionine e.g. in a ratio by weight of about 12:10: 100, stimulate the production of active lymphocytes.

Where the tissue of the human body is forced by irritation to an over-production of lymphocytes for a long period of time, the lymphatic ganglions may degenerate with a breakdown in the defensive mechanism of the body. Compositions according to the invention containing for example 2-thiouracil-4-carboxylic acid, uracil-4-carboxylic acid and methionine in a ratio by weight of about 1:10:100 have been found in these circumstances to promote a new formation of lymphocytes and thus to resuscitate the defensive mechanism of the body.

It has for example been demonstrated that a composition according to the invention containing 2- thiouracil-4-carboxylic acid, uracil-4-carboxylic acid and methioine in a ratio by weight of about 1:10:100 is useful in the treatment of virus warts and diseases such as for example Molluscum contagiosum, Condylomata acuminata, Herpes simplex and Herpes zoster. It also leads to an increase in the erythrocytes in the blood.

Thus thiouracil-carboxylic acids and nontoxic salts and alkyl esters thereof may be antimetabolites of uracil which are taken up by virus (pl.) and which stunt or inhibit the growth thereof.

Thiouracil-carboxylic acids are substances having generally low toxicity. Thus for example 2-thiouracil- 4-carboxylic acid has been administered orally to rats at a dosage of 0.5 g./kg. of body weight for over 90 days without any toxic effects. Further it has been shown that thiouracil-4-carboxylic acid has no influence on the activity of the thyroid gland and so it efiects neither the oxygen consumption of the body nor the basal metabolic rate.

The thiouracil-carboxylic acid (or nontoxic salt or alkyl ester thereof) is preferably administered at a dose of about 1 to 500 mg. advantageously to 50 mg., per day. When administered together with a uracil-carboxylic acid (or nontoxic salt or alkyl ester thereof), the latter is preferably administered at a dosage of about 50 mg. to l l g., advantageously 100 to 500 mg., per day. When administered together with methionine (or a biological equivalent thereof), the latter is preferably administered at a dosage of about 1 to 10 g., advantageously 3 to 5 g., per day.

The following examples illustrate the invention:

EXAMPLE 1 Gelatin capsules are prepared each of which contains the following ingredients:

Methionine 250 mg. Uracil-4-carboxylic acid 50 mg. 2-Thiouracil'4-carhoxylic acid 5-l0 mg.

The recommended dose is 4 or 5 capsules per day.

EXAMPLE 2 Ampuls are prepared each of which contains the following: 30 mg. of the choline salt of Z-thiouracil-4carboxylic acid 200 mg. uracil-4-carboxylic acid, choline salt 250 mg. dl-methionine The ingredients are filled into dry ampuls. In use, one gives 15 ml. sterile, physiological salt solution in the ampul and immediately after dissolution of the active ingredients, the ampul solution is injected (preferably subcutaneoysly).

EXAMPLE 3 Dietetic preparation mg. 2-thiouracil-4-carboxylic acid are homogeneously mixed in 100 g. milk powder. This mild powder is if desired made aromatic. In use, 20 g. of this powder may be dissolved in a cup of hot water and given one to two times daily.

I claim:

1. A pharmaceutical composition which comprises as active ingredients:

a. 2-thiouracil-4-carboxylic acid, or a nontoxic salt or lower alkyl ester thereof; and

b. uracil-4-carboxylic acid, or a nontoxic salt or lower alkyl ester thereof;

wherein the ratio by weight of component (a) to component (b) is about 1:10 and the weight of (a) per dosage unit is from 0.1 mg. to 100 mg.

2. The pharmaceutical composition of claim 1 which also contains methionine.

3. A method of providing a nonspecific activity against virus warts, Molluscum contagiosum, Condylomata acuminata, Herpes simplex, and Herpes zoster in humans which comprises administering thereto a pharmaceutical composition which comprises as active ingredients:

a. 2-thiouracil-4-carboxylic acid, or a nontoxic salt or lower alkyl ester thereof; and b. uracil-4-carboxylic acid, or a nontoxic salt or lower alkyl ester thereof;

in an amount sufficient to provide a dose of about I to 500 mg. per day of component (a), and a dose of about 50 mg. to l gm. per day of component (b), wherein the ratio by weight of component (a) to component (b) is from 1:1 to l: 50.

4. The method of claim 3 wherein the pharmaceutical composition also contains methionine.

5. The method of claim 3 wherein the dose of component (a) is 10 mg. to 50 mg. per day and the dose of component (b) is 100 mg. to 500 mg. per day. 

2. The pharmaceutical composition of claim 1 which also contains methionine.
 3. A method of providing a nonspecific activity against virus warts, Molluscum contagiosum, Condylomata acuminata, Herpes simplex, and Herpes zoster in humans which comprises administering thereto a pharmaceutical composition which comprises as active ingredients: a. 2-thiouracil-4-carboxylic acid, or a nontoxic salt or lower alkyl ester thereof; and b. uracil-4-carboxylic acid, or a nontoxic salt or lower alkyl ester thereof; in an amount sufficient to provide a dose of about 1 TO 500 mg. per day of component (a), and a dose of about 50 mg. to 1 gm. per day of component (b), wherein the ratio by weight of component (a) to component (b) is from 1:1 to 1:
 50. 4. The method of claim 3 wherein the pharmaceutical composition also contains methionine.
 5. The method of claim 3 wherein the dose of component (a) is 10 mg. to 50 mg. per day and the dose of component (b) is 100 mg. to 500 mg. per day. 